Rock-drill.



No. 690,687, 'Patented 1an. 7,' 1902.

(Appumian meamay '6, 1901.)

(-No Model.) .2 Sheets-Sheet I.

MMM/QW@ ""690687- Patente-d 1an. 7,1901.

A. M. BALLU.` y

BUCK DRILL., (Application med xly'e, i901.)

(no Model.) 2 sheen-sheet 2..

UNITED STATES PATENT EEICE.

ALVIN I vI. BALLOU, OF DENVER, COLORADO.

ROCK- DRILL.

SPZECIFIGATION forming part of Letters Patent No. 690,687, dated January 7, 1902.

Application filed May 6, 1901.

To all Ywhom t Wawy concern: v

Be it known that I, ALVIN M. BALLOU, a citizen of the United States of, America, and a resident of Denver, county of Arapahoe, and State of Colorado, have invented certain new and useful Improvements in Rock-Drills, of which the following is a specification.

The present invention relates generally to means for drilling rocks, and more particularly to an electric percussion rock-drill.`

The object of the invention is to provide a superior substitute for the ordinary air-d rill, but adapted to be operated by electric power with equal iiexibility of action and yefficient results. Obvious advantages follow from the nature of my invention as herein disclosed. The organization comprising the invention embraces leading features which are important singly and `in combination. Compactness is obtained by such a construction that both the motor and all the mechanism except the end of the drilling-tool are completely inclosed in and protected by a shell formed in two-parts clamped together. The motor is so located as to be in direct line of the blow of the drill. The exterior view resembles an ordinary air rockdrill and is mounted .in substantially the same manner upon a standard.

All drills are apt to stick in a crevice during opera-tion; but I have providedfor the automatic release of the kdrill by a shortening of the stroke without injury to the mechanism. By a combination of clutches,sprin gs,

and feeding devices I am enabled to drill rocks electromechanically in a practical, quick, and efficient manner without injury to the rockdrill. To this end the motor is geared, through an idle wheel, to a shaft which compresses a spring repeatedly and rapidly and automatically releases the spring to do the actual work of drilling, thereby throwing a substantially constant load upon the motor. To permit this action, I have a kind of compound clu'tch which will-release the drill intermittently, as the case requires.

The details are best understood by refer ence to the accompanying drawings.

Figure 1 is a central sectional elevation of the complete device. Fig. 2 is a centralsectional plan of said device. Fig. 3 is a crosssection at the line A B in Fig. 2. Fig. 4. is a perspective view of the drill mounted upon Serial No. 58,916. (No model.)

a standard ready for operation. Figs. 5, 6, 7, and 8 are different views of the clutch, which is also visible in Fig. 2. Figs. 9, 10, and 11 show the cross-'head and crank. Figs. 12, 13, and 14. show separate parts for turning the drill when driven forward by the spring.

The motor is represented at 1 and is provided on its shaft 2 with a driving-pinion 4', which rgears with an idle wheel 5, which in turn gears with a wheel 6, loose on the shaft '7. VThe Wheel 6 is, however, adapted to be locked to a disk 8 in the following manner: There are wedge-shaped or beveled keys 9 passing through thedisk 8 and projecting into tapered holes -10 in the disk 8, and these keys are pressed therein by springs 11,which arecarried on the disk 8. It is now evident that the rotation of the wheel 6 in the absence of too much resistance will cause the rotation of the disk 8, and for a reason now to be mentioned'the shaft 7,-with its crank 12, will also be rotated, because of the friction-rollers 13, which clutch'the shaft 7 in known principle of balls in a wedge-shaped opening between the shaft 7 and the disk 8.

The crank l2 is pivoted to the cross-head 14., which is movable on guides 15, which are on the inside of the shell or casing, formed in two parts 16 and 17. The pin of the crank 12 forvthis purpose passes through the block 18, movable up and down in the cross-head 14, which is connected to a plunger 19 by a rifled groove portion 20, having a rilied nut 2l surrounding it and held in the casing for the vpulpose of rotating the plunger 19 when propelled longitudinally. The plunger has a shoulder 22, between which and the casing is a spring 23, adapted to be com pressed when the plunger, with the tool 24, is drawn in.

25 is a link for fastening the cross-head 14 to the rifled portion 20.

Upon turning the armature of the motor by means of gearing 2 and 5 constantly rorates the wheel 6. The keys 9 are forced into the holes 9 in the wheel 6, thereby locking the disk 8 to the wheel 6, and the two rotate together. In view of the roller-clutch 13 the shaft 7 and crank 12 also rotate and draw inward the plunger 19 a full stroke, at the same one direction but not in the other by the well-l by an electric current the shaft 2 rotates and ICO til

time forcibly pressing the spring 23. This spring 23 maintains the shaft 7 clutched to the disk 8 until the plunger 19 has only just passed the center for the return stroke. Instantly the spring 23 pulls forward the crank 12, which causes a release of the friction-rolls 13 from the shaft 7, and the plunger therefore jumps forward with a drilling blow, and at the same time turns on its axis. Although the gear-wheel 6 continues to rotate, the shaftY its rotation, and if any tension had been placed upon the spring 23 the plunger 19 would he driven forward. The disk 8 would soon be in such a position Where it would be engaged with the Wheel 6 by means of the keys 9, and another pull would he applied to the drill, and this operation would be repeated until the drill was released.

It is evident that the springs 1l may be of such strength and so adjusted as not to cause an overload on the motor 1.

Should the operator not feed the drill fast enough by means of the handle 26, the spring 27 on the rifled portion 2O Will receive the shock of the link 25. On the other hand, if the operator feeds. the drill too fast no harm will he done, because I allow a certain play in link 25 at the connection of the cross-head 14 with the plunger.

The interior Vof the casing is divided into two parts by the webs l6and 17', separating the motor l from the rest of the mechanism, so that the same may operate in oil, if desired, so as to protect the armature and fieldmagnet.

28 represents bearings for the shaft 7, formed in the casing, and 29 similar bearings for the shaft 2.

I claim as my inventionl. In an electromechanical rock-drill, the combination of\a driving-wheel 6, having holes, a disk provided with loose tapered keys and with springs holding said keys in said holes, and a shaft, upon which said Wheel is loose and upon Which said disk is mounted with friction-rolls for permitting rotation in one direction and not in the other, a motor for driving said Wheel, a crank on said shaft, and a plunger for holding a bit connected up with said crank against the resistance of the spring.

2. An electromechanical rock drill, consisting of the combination of a driving-Wheel 6, having holes, a disk provided with loose tapered keys and with springs holding said keys in said holes, a shaft, upon which said wheel is loose and upon which said disk is mounted with friction-rolls for permitting rotation in one direction and not in the other, a crank upon said shaft, a plunger for holding a bit, a cross-head movable to and fro and connecting said crank to said plunger, means for rotating said plunger during its longitudinal movement, a spring acting to drive out said plunger and adapted to be compressed bythe turning of said crank, a link 25 connecting said cross-head to said plunger, and a spring 27 in front of said link to act as a cushion.

In testimony whereof I have hereunto subscribed my name this 27th day of April, 1901.

ALVIN M. BALLoU. [n s] 

